NFSv4: Unify synchronous and asynchronous error handling

They now only differ in the way we handle waiting, so let's unify.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

fs/nfs/nfs4proc.c

@@ -78,7 +78,6 @@ struct nfs4_opendata;
 static int _nfs4_proc_open(struct nfs4_opendata *data);
 static int _nfs4_recover_proc_open(struct nfs4_opendata *data);
 static int nfs4_do_fsinfo(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *);
-static int nfs4_async_handle_error(struct rpc_task *, struct nfs_server *, struct nfs4_state *, long *);
 static void nfs_fixup_referral_attributes(struct nfs_fattr *fattr);
 static int nfs4_proc_getattr(struct nfs_server *, struct nfs_fh *, struct nfs_fattr *, struct nfs4_label *label);
 static int _nfs4_proc_getattr(struct nfs_server *server, struct nfs_fh *fhandle, struct nfs_fattr *fattr, struct nfs4_label *label);
@@ -466,6 +465,55 @@ int nfs4_handle_exception(struct nfs_server *server, int errorcode, struct nfs4_
 	return ret;
 }
 
+static int
+nfs4_async_handle_exception(struct rpc_task *task, struct nfs_server *server,
+		int errorcode, struct nfs4_exception *exception)
+{
+	struct nfs_client *clp = server->nfs_client;
+	int ret;
+
+	ret = nfs4_do_handle_exception(server, errorcode, exception);
+	if (exception->delay) {
+		rpc_delay(task, nfs4_update_delay(&exception->timeout));
+		goto out_retry;
+	}
+	if (exception->recovering) {
+		rpc_sleep_on(&clp->cl_rpcwaitq, task, NULL);
+		if (test_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) == 0)
+			rpc_wake_up_queued_task(&clp->cl_rpcwaitq, task);
+		goto out_retry;
+	}
+	if (test_bit(NFS_MIG_FAILED, &server->mig_status))
+		ret = -EIO;
+	return ret;
+out_retry:
+	if (ret == 0)
+		exception->retry = 1;
+	return ret;
+}
+
+static int
+nfs4_async_handle_error(struct rpc_task *task, struct nfs_server *server,
+			struct nfs4_state *state, long *timeout)
+{
+	struct nfs4_exception exception = {
+		.state = state,
+	};
+
+	if (task->tk_status >= 0)
+		return 0;
+	if (timeout)
+		exception.timeout = *timeout;
+	task->tk_status = nfs4_async_handle_exception(task, server,
+			task->tk_status,
+			&exception);
+	if (exception.delay && timeout)
+		*timeout = exception.timeout;
+	if (exception.retry)
+		return -EAGAIN;
+	return 0;
+}
+
 /*
  * Return 'true' if 'clp' is using an rpc_client that is integrity protected
  * or 'false' otherwise.
@@ -4979,79 +5027,6 @@ nfs4_set_security_label(struct dentry *dentry, const void *buf, size_t buflen)
 #endif	/* CONFIG_NFS_V4_SECURITY_LABEL */
 
 
-static int
-nfs4_async_handle_error(struct rpc_task *task, struct nfs_server *server,
-			struct nfs4_state *state, long *timeout)
-{
-	struct nfs_client *clp = server->nfs_client;
-
-	if (task->tk_status >= 0)
-		return 0;
-	switch(task->tk_status) {
-		case -NFS4ERR_DELEG_REVOKED:
-		case -NFS4ERR_ADMIN_REVOKED:
-		case -NFS4ERR_BAD_STATEID:
-		case -NFS4ERR_OPENMODE:
-			if (state == NULL)
-				break;
-			if (nfs4_schedule_stateid_recovery(server, state) < 0)
-				goto recovery_failed;
-			goto wait_on_recovery;
-		case -NFS4ERR_EXPIRED:
-			if (state != NULL) {
-				if (nfs4_schedule_stateid_recovery(server, state) < 0)
-					goto recovery_failed;
-			}
-		case -NFS4ERR_STALE_STATEID:
-		case -NFS4ERR_STALE_CLIENTID:
-			nfs4_schedule_lease_recovery(clp);
-			goto wait_on_recovery;
-		case -NFS4ERR_MOVED:
-			if (nfs4_schedule_migration_recovery(server) < 0)
-				goto recovery_failed;
-			goto wait_on_recovery;
-		case -NFS4ERR_LEASE_MOVED:
-			nfs4_schedule_lease_moved_recovery(clp);
-			goto wait_on_recovery;
-#if defined(CONFIG_NFS_V4_1)
-		case -NFS4ERR_BADSESSION:
-		case -NFS4ERR_BADSLOT:
-		case -NFS4ERR_BAD_HIGH_SLOT:
-		case -NFS4ERR_DEADSESSION:
-		case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
-		case -NFS4ERR_SEQ_FALSE_RETRY:
-		case -NFS4ERR_SEQ_MISORDERED:
-			dprintk("%s ERROR %d, Reset session\n", __func__,
-				task->tk_status);
-			nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
-			goto wait_on_recovery;
-#endif /* CONFIG_NFS_V4_1 */
-		case -NFS4ERR_DELAY:
-			nfs_inc_server_stats(server, NFSIOS_DELAY);
-			rpc_delay(task, nfs4_update_delay(timeout));
-			goto restart_call;
-		case -NFS4ERR_GRACE:
-			rpc_delay(task, NFS4_POLL_RETRY_MAX);
-		case -NFS4ERR_RETRY_UNCACHED_REP:
-		case -NFS4ERR_OLD_STATEID:
-			goto restart_call;
-	}
-	task->tk_status = nfs4_map_errors(task->tk_status);
-	return 0;
-recovery_failed:
-	task->tk_status = -EIO;
-	return 0;
-wait_on_recovery:
-	rpc_sleep_on(&clp->cl_rpcwaitq, task, NULL);
-	if (test_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) == 0)
-		rpc_wake_up_queued_task(&clp->cl_rpcwaitq, task);
-	if (test_bit(NFS_MIG_FAILED, &server->mig_status))
-		goto recovery_failed;
-restart_call:
-	task->tk_status = 0;
-	return -EAGAIN;
-}
-
 static void nfs4_init_boot_verifier(const struct nfs_client *clp,
 				    nfs4_verifier *bootverf)
 {